Effect of biochar and soil amendment on bacterial community composition in the root soil and fruit of tomato under greenhouse conditions

Abstract Tomato root soil quality and microbial community composition are important for improving fruit quality. However, the effect of biochar and soil amendment on tomato fruit quality and root soil characteristics under greenhouse production has been insufficiently explored. In this study, the fruit quality and bacterial communities in tomato root soil and fruit subjected to biochar and soil amendment were analyzed using Illumina sequencing. The results showed that the application of biochar and soil amendment increased the available phosphorous in tomato greenhouse soils, ranging from 49.37 to 52.02 mg kg −1 . Biochar greatly affected the fruit quality, such as the lutein content (1.55 μg g −1 ). The potassium content in the fruits was higher than that of nitrogen and phosphorous, reaching 1.59 g kg −1 . The addition of biochar and soil amendment promoted the abundance of Bacteroidota, Actinobacteriota, and Firmicutes at the phylum level in the tomato fruits. However, biochar and soil amendment slightly reduced the number of Proteobacteria in the fruits. This study provides new insights into practical strategies for promoting tomato fruit quality and soil condition.